It's not just the London 2012 ones, either. Although they are terrible, in keeping with the atrocious logo that some drunk and spatially-challenged Briton appears to have scribbled on a napkin at a pub.
Even Athens, on whom you would think you could rely, Olympics-wise, had a pair of mangled and troubling globs who were suppose to represent divinities of unguessable identity. (Yes, if you look them up, they are supposed to be Athena and Phevos. Sure. Whatever. Greece, you pretty much invented naturalistic art. What is your problem?)
And here's the real question: why do the Olympics need a mascot? Why are the Olympics a brand? You know, besides that selling things makes money. There's a truce, you compete against other countries. If there has to be a brand, you're missing the point.
But even if you're missing the point, you could miss it by not quite that much.